June 21, 1889.] 



SCIENCE. 



491 



INDUSTRIAL NOTES. 

 Electric Shell Hoist for War-Vessels. 



We publish in this issue of our paper a view of one of the elec- 

 tric hoists built by the Sprague Electric Railway and Motor Com- 

 pany of New York, for the new United States cruiser " Atlanta." 

 This hoist is the first of its kind that has been built for this work, 

 and this commencement of the use of electric power on shipboard 

 is most novel, and promises to extend rapidly. The advantages of 

 electric power for the manifold uses on board vessels, over trans- 

 mission of power by steam to different portions of the vessel, are 

 many, and the general adoption of incandescent lighting on ship- 

 board enables such motors to be operated without additional dy- 

 namo installation. 



The hoist which we illustrate is of three horse-power, using the 

 regular Sprague graphite brushes, and can be run forwards or 

 backwards with the greatest facility by the simple movement in 

 one direction or another of an electric switch. By means of this 

 same switch the speed can be varied to any degree desired. 



Although built for the special purpose of hoisting shells, this 



New York, 50 incandescent ; Lawrence Line Company, Lawrence, 

 Mass., 50 incandescent ; Riverside Mills. Providence, R.I., 25 in- 

 candescent. 



The Complete Combustion Boiler. 



Mr. Francis E. Galloupe, mechanical engineer, tested the 

 evaporative performance of a loohorse-power steam-boiler having 

 the downward draught furnace, at the works of the Suffolk Cord- 

 age Company, Chelsea, .Mass., Feb. 25. 



The boiler tested was a horizontal, cylindrical, multitubular 

 boiler, and did not differ in design, either of the general construc- 

 tion or portions occupietl by the water and steam, from that of the 

 ordinary form, except in the furnace. The furnace is built of steel 

 plates riveted like those of the shell, and is placed entirely within 

 the shell of the boiler, and surrounded by water spaces. At the 

 back end of the grate a hanging water-leg of steel plates, riveted 

 to the crown sheet of the furnace, e.xtends downward to within 

 eighteen inches of the ash-pit or furnace bottom. The grate is 

 formed of water tubes entering the front side of the water-leg, at 

 the back end of the grate, at a moderate inclination from the hori- 



SI^KAGUE ELECTRIC SHELL HOIST. 



combination promises to meet a large demand for small hoists in 

 manufacturing and other industries, where the small space occu- 

 pied by an electric motor is quite a desideratum. 



The tendency among the leading electric supply companies seems 

 to be gradually towards electric motor combinations with other 

 machines, like the above ; and experience shows that such combi- 

 nations create a demand as their advantages become recognized. 



New Electric-Light Plants. 



The Thomson-Houston Electric Company reports the following 

 sales : Narragansett Pier, R.I., 30 arc, 1,000 incandescent ; Seattle, 

 W.T., 50 arc ; Brockport, N.Y., 20 arc ; Troy, O., 50 arc ; Somer- 

 ville, Mass., 100 arc; Binghamton, N.Y., 150 arc; Philadelphia, 

 Penn., 100 arc; Lowell, Mass., 50 arc ; Boston, Mass., 1,000 alter- 

 nating; Springfield, Mass., go arc; Minneapolis, Minn., 150 arc, 

 1,200 incandescent ; Rochester, N.H., 50 arc ; Chelsea, Mass., 100 

 arc ; Norwich, Conn., 400 incandescent ; Goldsboro, N.J., 45 arc, 

 600 incandescent ; Sorrento, Me., 30 arc. They also report the 

 following isolated plants : Wamsutta Mills, New Bedford, Mass., 

 400 incandescent ; I5ennett Manufacturing Company, New Bedford, 

 Mass., 600 incandescent ; Whittle & Hanrahan, Providence, R.L, 

 15 arc; H. Ricker & Sons, Poland Springs, Me., 12 arc; Jewell 

 Milling Company, Brooklyn, N.Y., 300 incandescent ; M. W. Hyer, 



zontal, and enters a gun-metal box in front, just below the furnace 

 doors. Return tubes, also inclined, extend from this box beneath 

 the great tubes back to the water-leg. and insure a circulation of 

 water from the main shell and water- leg, through the grate lubes. 

 The space beneath the grate, ordinarily the ash-pit, is the combus- 

 tion-chamber, the air for combustion being admitted through the 

 fire-doors above the grate, and drawn down through the grate-bars 

 by the chimney draught, where it becomes highly heated before or 

 during its combination with the hot gases from the coal. Beyond 

 the water-leg, extending up to the crown sheet of the furnace, is an 

 extension of the combustion-chamber, which forms the passage to 

 the tubes, the tube sheet being eighteen inches horizontally from 

 back of the water-leg. The hot gases pass from this point through 

 the tubes, which form a large absorbing area, directly to the uptake 

 and chimney. 



The position and arrangement of the furnace resemble that in 

 the locomotive boiler, with the addition of a deflecting arch, which 

 tends to mix the hot gases on their way to the tubes, and, as would 

 be expected from this construction of an internal furnace entirely 

 surrounded by the water-heating surfaces of the boiler, the boiler 

 made steam very quickly, and almost immediately on lighting the 

 fire. 



During the trial a large Brown engine, stated to have been de- 

 veloping about 210 horse-power, was run by the steam from the 



